The present invention relates to systems and methods for acquiring data and conducting analysis using photoacoustic spectroscopic sensing.
There are a variety of invasive and non-invasive imaging modalities in clinical use. Some have received general and substantially wide adoption for a variety of clinical applications, such as computed tomography (CT) imaging, ultrasound imaging, magnetic resonance (MR) imaging, and positron emission tomography (PET) imaging. These and other imaging modalities have been highly-specialized for particular clinical applications.
Ultrasound imaging is used in a variety of ways, including some that may be tailored to specific clinical applications. Traditional ultrasonic scanning and imaging techniques rely on an ultrasound signal that is delivered into an area of interest to interrogate the area. There are a number of modes in which traditional ultrasound system operate to produce interrogate objects. An ultrasound transmitter may be placed on one side of the object and the ultrasound signal transmitted through the object to an ultrasound receiver placed on the other side (“transmission mode”). With transmission mode methods, an image may be produced in which the brightness of each pixel is a function of the amplitude of the ultrasound that reaches the receiver (“attenuation” mode), or the brightness of each pixel is a function of the time required for the sound to reach the receiver (“time-of-flight” or “speed of sound” mode). In the alternative, the receiver may be positioned on the same side of the object as the transmitter and an image may be produced in which the brightness of each pixel is a function of the amplitude or time-of-flight of the ultrasound reflected from the object back to the receiver (“refraction”, “backscatter” or “echo” mode). In either case, ultrasound signals are transmitted into the object being investigated and an ultrasound signal (transmitted signal or echo) is received to acquire the data.
In addition to these traditional imaging modalities, there are new and emerging imaging modalities. Some are hybrids of existing modalities, such as combined CT-PET or MR-PET systems. Others are new modalities or employ different or modified contrast mechanism and, thereby, provide unique clinical information.
Unfortunately, regardless of the diversity of the imaging modalities available or the combinations of known imaging modalities, each modality or hybrid of modalities has inherent limitations. Some limitations may include health limitations, such as with imaging modalities that utilize ionizing radiation. Other limitations may be inherent in the contrast mechanism employed by the modality.
Thus, there is a need for systems and methods capable of providing diverse and accurate clinical information about in vivo structures noninvasively in an efficient and effective manner.